Heat the oil in a saucepan over medium heat until hot, then add the green onions and saute until softened, about a minute. Add the garlic and chile flakes and saute for 30 seconds.
Add the orzo, salt and pepper to the pan and toss to coat the grains, a minute or two. Add the warmed broth and gently stir. Allow the broth to come to a simmer, then cook for 5 minutes.
Add the asparagus, broccolini, zucchini and peas. Stir and cook for another 2 minutes. Add the kale, Parmesan and lemon zest and give it a good stir, then allow to cook for another 2 minutes.
Add the herbs and stir to combine. Serve in bowls topped with Parmesan and additional herbs.